unit 15 osborne book
meibaker
Registered Posts: 481 Dedicated contributor 🦉
i am having problems with 3.3 on p81. how to forecast the cash sales. thanks
0
Comments

Hi Meibaker,
Based on the moving averages calculated in a you can see that the sales go up with £ 5 each day. The seasonal variations can be calculated based on that too. Based on those figures you can calculate the new figures for week 4.
There is a short explanation of how to calculate it in the time series analysis on page 6871 including the formula of y = mx + c.
The workings for this one work out for me as:
The moving averages are calculated on a five point moving average, that means the first one we can calculate is the Thursday in week 1.
Thursday is 915 (Tue wk1) + 960 (Wed wk1) + 1040 (Thu wk1) + 1080 (Fri wk1) + 1080 (Sat wk1) / 5 = 1015
Then the next is Friday in week 1. The same principle applies. You pick the Wed wk 1, Thu wk1, Fri wk 1, Sat wk 1 and Tue wk 2 (1040 + 1080 +1080 +940 +985) divide it by 5 and this comes to 1020.
This just moves on one day at the time and you keep dropping the last day and adding a new one, till you run out of groups of 5, which is at the Wednesday in week 3.
Now if you put them all underneath each other, you can see that this moves up 5 every day.
The next step is the seasonal variations. You calculate these by going calculating the original sales of the day minus the average you just calculated.
For Thursday in week 1 this is 1040  1015 = +25
For friday in week 1 this would be 1080  1020 = +60
If you do this for all the averages you calculated you find that on the Thursday the seasonal variation is +25, for Friday this is +60, for the Saturday +55, the Tuesday is then 90 and the Wednesday 50.
Now to come to the sales of the new week, the formula in the book given is y = mx + c
y is the forecast
m is the daily increase of 5
x is the number of days since the start (using the moving averages, so Thursday)
c is 1015 which is the starting figure and the first moving average we calculated.
This means for week 4, for the Tuesday the forecast is 13 x 5 + 1015 = 1080
For Wednesday this is 14 x 5 + 1015 = 1085
For Thursday this is 15 x 5 + 1015 = 1090
For Friday this is 16 x 5 + 1015 = 1095
For Saturday this is 17 x 5 + 1015 = 1100
These are the figures without seasonal variations however.
We can add those by just adding the figures we calculated as seasonal variations:
Tuesday 1080  90 = 990
Wednesday 1085  50 = 1035
Thursday 1090 + 25 = 1115
Friday 1095 + 60 = 1155
Saturday 1100 + 55 = 1155
I hope this helps!
Thanks,
Rinske0 
hi rinske:
thanks so much for your explanation, your explanation are a lot better than the books. i am so grateful for your help! thanks again
may x0 
hi rinske:
thanks so much for your explanation, your explanation are a lot better than the books. i am so grateful for your help! thanks again
may x
I was in doubt whether to post this, since the explanation looked like a lot of text again, but I also didn't see the use of posting it without workings, because then you might still get stuck as in how to get there.
Are you studying the diploma pathway or NVQ? And do you have a provider for support or did you just buy the books?0
Categories
 All Categories
 1.2K Books to buy and sell
 2.3K General discussion
 12.5K For AAT students
 315 NEW! Qualifications 2022
 160 General Qualifications 2022 discussion
 11 AAT Level 2 Certificate in Accounting
 56 AAT Level 3 Diploma in Accounting
 85 AAT Level 4 Diploma in Professional Accounting
 8.8K For accounting professionals
 23 coronavirus (Covid19)
 272 VAT
 92 Software
 273 Tax
 135 Bookkeeping
 7.2K General accounting discussion
 200 AAT member discussion
 3.8K For everyone
 38 AAT news and announcements
 345 Feedback for AAT
 2.8K Chat and offtopic discussion
 582 Job postings
 16 Who can benefit from AAT?
 36 Where can AAT take me?
 42 Getting started with AAT
 26 Finding an AAT training provider
 48 Distance learning and other ways to study AAT
 25 Apprenticeships
 66 AAT membership